Could AI kill the joy of competitive sports and games?
Unlikely! 

Chess has been "solved" by AI much longer than GO (chess engines even before AI are way too strong for human players) and still people are playing and competing.

Simply put competition and sports live from the human element. Humans competing against each other will still create the same joy for most people regardless of the fact that all involved players might lose against a computer. 

Some select individuals on the highest level might be put off by the new reality but it won't be the end of competition. 

No human is faster than a car and yet we still celebrate running competitions.

Indeed I think long-term we will gain entertainment by watching different AIs and models compete against each other in chess or Go.